The use of energy dissipating materials, such as plastic foam, in connection with energy absorbing vehicle components is well known. For example, U.S. Pat. No. 3,888,502, issued to Felzer et al, discloses various energy absorbing vehicle components comprising a hollow elongated metal member having straight walls and a uniform cross section filled with foamed plastic material. These hollow metal components filled with foamed plastic material may be located on a vehicle where energy absorbing elements are required and provide a controlled, even plastic deformation of selected vehicle components, thereby optimizing the energy absorbed by the vehicle due to impact forces resulting from collision.
However, these energy absorbing components are, by design, destroyed to some extent as a result of collision impact forces.
Moreover, it is often difficult to alter the design of existing vehicles in order to achieve the energy absorption efficiency attained by these components.
It is therefore one object of the present invention to provide an energy absorbing steering assembly which provides controlled absorption of energy under impact conditions.
It is another object of the present invention to provide an energy absorbing steering assembly including means for reducing the "G" force loading on the driver caused by the impact force of the driver on the steering wheel during a collision.
It is another object of the present invention to provide an energy absorbing steering assembly which allows for a limited, recoverable displacement of the steering column under impact load conditions below a preselected threshold.
It is yet another object of the present invention to provide a recoverable, energy absorbing steering assembly which can be quickly and easily adapted to existing vehicle steering column designs.